They = They? Are they HAM? Are "they" 2? 3? 4? 5? 6-10? 11-20? 21-50? 50-100? 100-1000? More than 1000? Are they all alive immediately before getting the opposite? Immediately after getting the opposite? Does anyone die because they got the opposite?

Did they want some tangible item(s)? Money? An information? Some kind of declaration or acknowledgement? Some legal position (other than becoming the owner/possessor of a tangible item or money)? Some kind of work done? Some physical or mental state? See something? Hear something?

Did they expect someone to give them what they wanted? To help them to get what they wanted?

Did all of "them" want the same? Did they cooperate to get it? Or was there some kind of rivality between them?

Did they expect to get what they wanted? Did they know there was a risk they would get the opposite?

They = They? Are they HAM? Yes. Are "they" 2? 3? 4? 5? 6-10? 11-20? 21-50? 50-100? 100-1000? More than 1000? Difficult to say...assume 1 or 2 were directly responsible, out of hundreds or thousands. Are they all alive immediately before getting the opposite? Yes.Immediately after getting the opposite?Yope - depends on how you look at it Beware of FAs. Does anyone die because they got the opposite? Yes.

Did they want some tangible item(s)? Noish. Money? An information? Some kind of declaration or acknowledgement? Some legal position (other than becoming the owner/possessor of a tangible item or money)? Some kind of work done? Some physical This. or mental state? See something? Hear something?

Did they expect someone to give them what they wanted? To help them to get what they wanted? No to both.

Did all of "them" want the same? Yes. Did they cooperate to get it? Or was there some kind of rivality between them? Probably both.

Did they expect to get what they wanted? Yes. Did they know there was a risk they would get the opposite? Maybe - but nothing like what they did get.

Did they want eternal life in the form of an afterlife? Becoming "immortal" due to their fame? Or simply living eternally more or less in the form they were living before? This.

Do all persons in the group of hundreds or thousands die because of the incident? No.

Does "getting the opposite" necessarily include dying? No. So they are by definition dead immediately after getting the opposite? No. But the relevant incident may have occured a while before? Irr.

Did all of the hundreds or thousands actively do something to get eternal life? Yes. The one or two persons directly responsible? Yes.

Is it relevant that "they" are all male? Noish. Are only the persons directly responsible HAM or also all of the hundreds or thousands? Assume that they were all HAM. Are there other relevant persons? Yes.

Did they expect to live eternally no matter what would happen in future? Or only not to die of old age or sickness with the possibility of a violent death or suicide still open?

Did they expect to become immortal by divine intervention? By magic? By technical means and/or medical measures? Or did they think that living eternally is just natural (so people only die because of an unnatural lifestyle)?

Did the one or two persons directly responsible something else than the hundreds or thousands? If yes: Were they expected to do so?

Are the other relevant persons HAM? Are these persons actively involved in making sure "they" get the opposite? Or are they trying to help "them"? Do these persons even know what "they" are doing? Why "they" are doing it?

did "they" expect eternal life as some kind of reward for actions in this life? suicide bombers relevant? Hashishin (the hash-eating assassins, expecting seventy-two virgins - note: gender unspecified! poor lads are likely in for a surprise...)? other cults/religious groups relevant?

Did they expect to live eternally no matter what would happen in future? Or only not to die of old age or sickness with the possibility of a violent death or suicide still open? This, probably.

Did they expect to become immortal by divine intervention? By magic? By technical means and/or medical measures? Or did they think that living eternally is just natural (so people only die because of an unnatural lifestyle)? Medical measures.

Did the one or two persons directly responsible something else than the hundreds or thousands? If yes: Were they expected to do so? They did the same general thing.

Are the other relevant persons HAM? H, all ages, both sexes - explore Are these persons actively involved in making sure "they" get the opposite? Yope. Or are they trying to help "them"? No. Do these persons even know what "they" are doing? Irr. Why "they" are doing it? Irr.

did "they" expect eternal life as some kind of reward for actions in this life? No.suicide bombers relevant? Noish.Hashishin (the hash-eating assassins, expecting seventy-two virgins - note: gender unspecified! poor lads are likely in for a surprise...)? Haha, no nothing like that.other cults/religious groups relevant? No.

The one or two persons: did they make a mistake? Convince others to do something which turned out to be contraproductive? Did these persons die as a result of their attempts to become immortal? Did anyone else die?

The hundreds or thousands: Did they know the one or two persons? Did they consider them to be experts? Leaders?

The other relevant persons: Do they have in common their profession? Another social role? Nationality? Are they working together? Do they also try to become immortal?

Medical measures - surgery? pharmaceutics? This is closest. megadoses of nutrients? genetic engineering? cryotechics? something usually considered as "alternative medicine"?

The one or two persons: did they make a mistake? Yes, for svv of "mistake" Convince others to do something which turned out to be contraproductive? No - I think they actually warned others not to try what they did. Did these persons die as a result of their attempts to become immortal? Who? Some of the hundreds or thousands probably died from what they did to become immortal. Did anyone else die? Yes, as a result of what the 1-2 persons did.

The hundreds or thousands: Did they know the one or two persons? Irr. Did they consider them to be experts? Leaders? No, peers if anything.

The other relevant persons: Do they have in common their profession? Another social role? Nationality? Are they working together? Do they also try to become immortal? No to all - to safe you from FAs: The other relevant persons are humanity in general.

So up to thousands of people died because they ate something that was supposed to prolong their life? No.

One or two were "directly responsible" for these deaths?No, they were not responsible in any way for thise deaths. by fooling people to take this medicine? No.

To clear up an apparent FA: No medicine is directly involved in the puzzle, although it's what they (the 100s-1000s of people) were trying to make (for svv of "medicine"). The ones that did get sick or die, did so from their own attempts at this "medicine".

Did the one or two persons bring up the idea that the "medicine" would make immortal? Did they want to do so? Or were their actions misunderstood? Did they believe the medicine would make immortal? Did they make the medicine themselves? Did they take it themselves? Give it to others?

Those who got sick or died: Were they harmed by taking the medicine (or what they supposed to be it)? Or in the process of producing the medicine? Of obtaining material (Ingredients? Equipment? Recipes?) for producing it?

Did the one or two persons bring up the idea that the "medicine" would make immortal? No. Did they want to do so? The idea existed already. Or were their actions misunderstood? No. Did they believe the medicine would make immortal? FA: They tried to make "medicine" to make themselves immortal, but they ended up making something else. What they made can not be classed as medicine and was not used as such. Did they make the medicine themselves? They made the non-medicine themselves. Did they take it themselves? Give it to others? FA - they did not make medicine.

Those who got sick or died: Were they harmed by taking the medicine (or what they supposed to be it)? Or in the process of producing the medicine? Of obtaining material (Ingredients? Equipment? Recipes?) for producing it? Probably all of the above. To clarify/recap: The hundreds or thousands were a group of people trying to find a formula for immortality. Some of them undoubtedly got sick or even died from their concoctions. The one or two made something that turned out not to be a formula for immortality, and they didn't try to use it as such, but it's possible they were injured by it. Other people died from it.

***SPOILER*** Chinese alchemists were trying to create an elixir of immortality, when they inadvertently stumbled upon the formula for gunpowder. Instead of leading to eternal life, their creation became a tool for death and destruction throughout the world for centuries to come.